yellowing
v. （使）变黄；（尤指由于年久）发黄（yellow 的现在分词）
例句
The underlined word "remunerated" in the passage means "Many people believe that yellowing and wetness are the greatest enemies of stamps".
文中带下划线的“酬劳”一词的意思是“许多人认为发黄和潮湿是邮票最大的敌人。”
The leaves of the trees are yellowing.
树叶在变黄。
That's far uglier than a yellowing lawn.
这远比黄色的草坪更难看。
